Conventional foil presses provide a constant and brief contact period of the honeycomb plate to the die, which is mounted on the platen. This period of high pressure contact, dwell time, is conventionally very brief, less than 0.25 seconds. Conventional foil stamping and embossing presses such as a 14×22 EHD (KLUGE, St. Croix Falls, Wis., US), for example, may have two possible press configurations, where each configuration yields a constant and short dwell time. Exemplary conventional dwell times are a first dwell time in a first configuration of less than 0.2 seconds and a second dwell time commensurate with the second configuration adding less than 0.2 seconds to the first less than 0.2 seconds.
FIG. 1A shows a conventional 14×22 EHE press with computer control from a right front perspective view. The entire press is driven from a single motor connected to a drive shaft via a belt and pulley. Cams, cranks, gears, chains, arms, belts, pulleys, valves, and solenoids are used to move different parts of the press assembly at the desired time and are driven from and/or timed from the aforementioned motor driven shaft. The press also employs a source of compressed air, which drives various suction and blowing devices on the press. Activation of pneumatic devices is also timed with or activated from the drive shaft and coordinated with the press's moving parts. A typical air pressure requirement is 90 PSI and a regulator assures the desired PSI is supplied to the press's pneumatic parts. Turning to FIG. 1A, guard plates 110 and grills 111 cover many of the key components in such a press, and these components are not visible in FIG. 1A. An automatic feed assembly 115 is shown at a top in the front 121 of the press 100 with pair of drive chains 141. Controls and indicators 117 are shown in the left front 120 foreground. Opposite the front 121 of the press a small portion of the back 121 of the press is visible. An exemplary air pressure regulator 131 is shown with associated pneumatic hoses 132.
FIG. 1B shows a left perspective view of a conventional 14×EHE. Safety grills 111 and safety guards 110 are shown spanning the left side from back 121 to front 120 of a conventional press 100. User controls 117 are provided in the foreground. And the feed system 115 is shown, again, here in the top front 120.
FIG. 1C shows a representative drawing of a conventional drive shaft and its two end flywheels, in accordance with a conventional press. A contrast between a conventional drive shaft, FIG. 1C with a drive shaft assembly in accordance with an embodiment of the present invention, shown in FIG. 12B, is described below. Turning to FIG. 1C, the drive belt 157 rests in the circumferential channel 156 of the left most 151 flywheel and serves as the drive flywheel 150. The far right 152 shows another flywheel upon which a pneumatic brake 162 is mounted. This brake 162 is applied to this far right 152 flywheel 160 when the stop button, not shown, is depressed by the user or if triggered for safety. The far right 152 flywheel 160 connects to the drive shaft 155 but does not connect to any pulleys or cams.
FIGS. 2A-2C show the feed assembly early in a cycle and the delivery assembly in an early and late part of a given cycle, respectively, from a top perspective view in a conventional 14×22 EHD press. The entire press cycle is driven, coordinated, and timed from the motor driven single drive shaft, Turning first to FIG. 2A, A blank 2-150 is retrieved from the feed magazine 2-115. More particularly, feed heads 2-130 attach to a feed bar 2-110 and move in parallel. Suction cups 2-140 attach to the heads 2-130 and pick up the blank 2-150. Air lines 2-120 apply and release suction to the heads 2-140. The heads 2-130 and the bar 2-110 move via pivot feed arm 2-170. A blank 2-150 is picked from the magazine 2-115 and the pivot feed arm 2-170 moves to bring the blank along trajectory 2-164. This trajectory 2-164 is shown in the blank 2-150 path and relative to the directions X-Y-Z 160, 161, 162, and 160. In accordance with a conventional press, the blank moves along the X-Z plane 2-161, 2-163 as a blank 2-150 is loaded on die mounted to the platen, not shown, and suction releases. In practice, foil rests on the honeycomb surface, not shown. The honeycomb closes on the die mounted on the platen, not shown, stamping the blank with foil in the desired die pattern.
FIG. 2B shows an early state of delivery in a given pressing cycle with the delivery system over the platen and the feed system just starting its approach with a blank to the platen. The feed heads 2-130, air lines 2-120, and feed suction heads 2-140 are shown with a subsequent blank 2-150-1. The feed bar, 2-110 shown in FIG. 2A, is not shown in FIG. 2B. Air lines 2-125 attach to delivery heads 2-135 and the heads have moved forward across the open platen 2-175. A delivery bar 2-117 attaches to the heads 2-135 and the heads move in parallel. FIG. 2C shows a late state of delivery in a given pressing cycle, the foil stamped blank already retrieved from the platen. Delivery heads 2-135 have rescinded from over the platen 2-175-f. Suction delivery heads 2-145 are shown at the end of the delivery heads 2-145 and grasp a foil stamped blank 2-155. The delivery arm 2-170 has moved over the platen face 2-175-f. 
FIGS. 3A to 3C show a front perspective view of a conventional press under a foil stamping application. FIG. 3A shows the honeycomb plate just about to close on the platen. FIG. 3B shows the honeycomb plate closed on the platen and FIG. 3C shows the honeycomb lifted back off the platen. A blank is fed from the feeder, shown in FIG. 2A, and slid to butt against a mounting strip on the platen face 2-175-f, shown in FIG. 2B. Turning to FIG. 3A, the honeycomb 3-190-a rotates and translates forward with the drive shaft and its face 3-190-f comes to press upon the platen face, where FIG. 3A shows the back of the platen 3-175-b. Foil 3-160 rotates across the face 3-190-f of the honeycomb plate. Guards 3-111 are shown in the foreground. The platen remains stationary.
The speed and precision of a conventional foil stamping press is rapid and exacting. The foil supply rests upon the honeycomb surface facing the platen. The die for the desired stamp is secured to the platen, facing up. The blank is positioned upon the die and as the honeycomb closes upon the platen, the foil contacts the blank and as pressure is applied, the foil stamps onto the paper in die form. The honeycomb retracts and a delivery arm 2-117, shown for example in FIG. 2B, retrieves the stamped image clearing the platen surface 2-175-f, also shown in FIG. 2B. This high speed and precision of a conventional press will add to the challenge of altering a given cycle. A conventional 14×22 EHx, where x may be E, D, or F, can be equipped with three foil rewind clutches. The conventional foil system provides reliable foil draws with accuracy for image spacings across blanks of 0.125 inches.
Turning to FIG. 3B, the honeycomb plate has closed upon the platen plate, where the top of the honeycomb top 3-190-t is shown with the back of the platen 3-175-b. Guard rails 3-11 are shown in the foreground and the foil supply 3-160 disappears from view between the honeycomb top 3-190-t and the platen 3-175-b. In FIG. 3C, the honeycomb 3-190-a has opened up from the platen and the platen face 3-175-f and the honeycomb face 3-190-f are shown. The foil supply 3-160 is shown here against the face of the honeycomb 3-190-f and extending from the honeycomb top 3-190-t. Guard rails 3-111 are shown in the foreground.
It may be desirable to decrease a necessary impact and pressure for a given die size under foil stamp operation. It may be desirable to increase the service life of these large, heavy, costly presses. It may be desirable to enable foil stamping with a large die size, e.g. greater than 40 inches squared, on a 14×22 EHD press.
In a conventional 14×22 press, the reconfiguration to achieve the increased dwell time may take a user in excess of one-half of one manhour. Although newer conventional KLUGE machines, such as Brandjten enabled machines described below, may take less time to reconfigure to the longer dwell time, the additional dwell time is less than 0.2 seconds. The dwell time is set by the press configuration and cannot be varied for a given press configuration. The impact force, is also relatively constant across a first configuration and a second increased dwell configuration.
An adjustable dwell time is also taught by Brandtjen, Jr., et al. (U.S. Pat. No. 6,935,228). Brandtjen teaches parallel movable arms on either side of a moveable platen plate, or honeycomb plate, and a stationary fixed platen plate. Springs in parallel with the axis of each respective movable arm absorb translation energy of the driven arms to enable the movable honeycomb plate and the stationary platen to remain in contact under compression for a period of time slightly longer than the dwell time afforded in the absence of compressible springs. The springs on a 14×22 EHD can double the dwell for a given run speed in the absence of using said springs. Such conventional springs are briefly shown in and described below in relation FIG. 4. As a particular example, a 3000 image per hour (IPH) non-spring enabled cycle can be extended by 61 milliseconds in the presence of compressible springs. Brandtjen teaches a typical 1 ton per die square inch for satisfactory foil stamping and a maximum tensile strength on a honeycomb connecting arm approaching 45 tons. This maximum compression force of 45 tons a would yield a maximum die image size of 45 inches squared on a medium [14×22] press. The 14×22 EHD can double the dwell time by using the springs without decreasing the IPH, the running speed. As another example, the dwell time for 1500 IPH may be 0.12 seconds.
FIG. 4 shows one of two parallel moveable arms 4-400 in a conventional no dwell state, where the springs 4-410 neither compress nor expand during pressing as the framed space, spring window 4-415, is secured across the cylindrical spacer 4-420. The spring window 4-415 is reduced in height 4-425c, Z direction 4-206, by a block 4-470. In turn, both cylindrical spacer 4-420 and parallel springs 4-410 span the height 4-425c of the window 4-415, forming a solid arm. An adjustment 4-430 readily reconfigures the arm 4-400 into a spring compressible position. Raising 4-422 the cylindrical spacer to position 4-421, the springs 4-410 extend past the spacer 4-420. Conventionally, an extended spring configuration can increase the dwell time in a conventional foil press as described above.
Still other conventional presses have attempted to increase dwell time on a foil stamping press by using a clutch and brake system. Biron (U.S. Pat. No. 3,412,678) teaches a mounting plate to which a die is mounted and a platen plate onto which a blank is fed with dual magnetic clutches.
Conventional presses can also provide adjustable temperature settings to facilitate a desired foil stamp design, foil type, or press speed. Changing the heat/temperature of the die alone in a conventional 14×22 EHx may have only a small effect on a typical foil stamping result.
It may be desirable to increase the working life of a given press. It may be desirable to be able to increase the die image size that can be created on an existing automatic foil stamping press. A given press would be more versatile if the range of die sizes that can be foil stamped is increased. It would be desirable if any user made adjustments to a press in field applications were user friendly.